New perspectives on the energy return on (energy) investment (EROI) of corn ethanol

Research on corn ethanol is overly focused on whether corn ethanol is a net energy yielder and, consequently, has missed some other fundamental issues, including (1) whether there is significant error associated with current estimates of the EROI of corn ethanol, (2) whether there is significant spatial variability in the EROI of corn ethanol production, (3) whether yield increases will translate linearly to increases in EROI, (4) the extent to which assumptions about co-product credits impact the EROI of corn ethanol, and (5) how much of the ethanol production from biorefineries is net energy. We address all of these concerns in this research by: (1) performing a meta-error analysis of the calculation of EROI, (2) calculating the EROI for 1,287 counties across the United States, and (3) performing a sensitivity analysis for the values of both yield and co-products within the calculation of EROI. Our results show that the average EROI calculated from the meta-error analysis was 1.07 ± 0.2, meaning that we are unable to assert whether the EROI of corn ethanol is greater than one. The average EROI calculated across 1,287 counties in our spatial analysis was 1.01, indicating that the literature tended to use optimal values for energy inputs and outputs compared to the average conditions across the Unites States. Increases in yield had a trivial impact on EROI, while co-product credits had a large impact on EROI. Based on our results from the spatial analysis and the location of biorefineries across the United States, we conclude that the net energy supplied to society by ethanol is only 0.8% of that supplied from gasoline. Recent work indicates that only energy sources extracted at EROIs of 3:1 or greater have the requisite net energy to sustain the infrastructure of the transportation system of the United States. In light of this work, we conclude that production of corn ethanol within the United States is unsustainable and requires energy subsidies from the larger oil economy.     

Discerning the factors explaining the change in energy efficiency

Due to the high rates of energy consumption and its impact on environment over the last decades, policy decision-makers are increasingly recognising the need to take actions that allow to address problems associated with the deployment of non-renewable resources and climate changes. One field of action has been the promotion of measures that contribute to improve energy efficiency of countries. The purpose of this study is to identify the main factors explaining changes in energy efficiency applying the multiplicative Log Mean Divisia Index decomposition method for a set of countries (Portugal, UK, Brazil and China) with different socio-economic background and energy mix. The results show that overall energy efficiency trends display different patterns between countries and the same happens within each country from a sectoral perspective. Major drivers of improvements of overall energy efficiency were the intensity effect and the affluence effect, whereas the driver that hampered those improvements was the energy consumption per capita. Some policy implications derived from the results achieved are: policy decision-makers should support measures that promote the adoption of energy-saving technologies resulting from new technological developments; policy measures should be directed to raise awareness of end-users regarding energy efficiency and energy conservation efforts; policy measures promoting economic growth through the development (or expansion) of sectors of activity that consume less energy can also be implemented; finally, policy instruments may also be used to reduce the costs of implementing energy efficiency and energy-saving measures to households and firms.     

The impact of energy awareness on energy efficiency

The increasing levels of global warming, depleting sources of fossil fuels and increasing energy costs are all having a large detrimental effect on today's society. Many efforts are being made to try and increase energy efficiency all over the world. One of the major problems is unnecessary and excessive energy utilisation. This problem has been identified by Loughborough University and they are making efforts to try and reduce energy wastage. One of their strategies, used up until recently, involved increasing energy awareness within students in halls of residence by means of a reward system called the Residential Halls Energy Efficiency League (Imago Services, Loughborough Students Union, Estates Services 2006). This scheme managed to reduce energy consumption by up to 10%, saving an estimated £9000 in only 52 days. Can those results be improved by targeting students more specifically? How much energy can be saved by increasing energy awareness?     

A reassessment of energy and GDP relationship: the case of Australia

This paper investigates the long- and short-run relationships between energy consumption and economic growth in Australia using the bound testing and the ARDL approach. The analytical framework utilized in this paper includes both production and demand side models and a unified model comprising both production and demand side variables. The energy–GDP relationships are investigated at aggregate as well as several disaggregated energy categories, such as coal, oil, gas and electricity. The possibilities of one or more structural break(s) in the data series are examined by applying the recent advances in techniques. We find that the results of the cointegration tests could be affected by the structural break(s) in the data. It is, therefore, crucial to incorporate the information on structural break(s) in the subsequent modelling and inferences. Moreover, neither the production side nor the demand side framework alone can provide sufficient information to draw an ultimate conclusion on the cointegration and causal direction between energy and output. When alternative frameworks and structural break(s) in time series are explored properly, strong evidence of a bidirectional relationship between energy and output can be observed. The finding is true at both the aggregate and the disaggregate levels of energy consumption.     

Empirical assessment of sustainable energy markets in the EU-28

Sustainable consumption and production policies have been developed by the EU as part of the United Nations 10-year framework programme on sustainable consumption and production. In this context, the study of energy consumption and production patterns might be especially relevant as the importance of energy input. This paper develops the Sustainable Energy Market Aggregated Index in the EU-28 that provides information about the achieved effects of sustainable consumption and production policies on energy efficiency, energy dependence, generation mix based on clean production technologies and competitive market structure. The results suggest that Denmark, Sweden, UK, Italy, the Netherlands have the better scores. Reinforcing measures are proposed for member states with the lowest results (Slovakia, Luxembourg, Estonia, Czech Republic and Belgium) in order to move towards more competitive energy markets.     

Progress in renewable energy

This paper provides an overview of some of the key technological and market developments for leading renewable energy technologies--wind, wave and tidal, photovoltaics (PV) and biomass energy. Market growth, innovation and policy are closely interrelated in the development of renewables and the key issues in each area are explored for each of the main types of renewable energy technology. This enables the prospects for future development and cost reduction to be considered in detail. Key issues for policy are outlined.     

Starting with the answers, perceptions about energy system risks

Persistent social conflict over energy issues, and gaps in perception among energy researchers, led the author to seek a top-down model that would adequately describe these phenomena. The model chosen (grid-group model of the cultural anthropologist) is called the cultural bias model by the author, and it describes several clusterings of human values (cultural categories). This model is used to give insight into these conflicts, and is also used to explain perceptions of risks. The idea of what constitutes a problem (or risk) and what constitutes a solution, is strongly dependent on the cultural category of the individual. Rather than seek out who is right and who is wrong, the author suggests a multirationality view of energy conflicts as a first step to better analysis and to conflict resolution.     

Changing energy intensity in China:a decomposition analysis

This study proposed a decomposition method based on the normalized quadratic shadow unit cost function to explore the determinants of the change in energy intensity in China from 1985 to 2010.The decomposition analysis indicates that (1) the improvement in technical efficiency dramatically reduced the energy intensity,whereas technological change played only a minor role,which could be attributed to a rebound effect;(2) the aggregated allocation effect was small because the change in the allocative distortion between capital and energy significantly enhanced energy intensity but was partly offset by the effect stemming from the change in the allocative distortion between capital and energy;and (3) the substitution of energy for labor increased energy intensity,but the aggregated substitution effect significantly reduced energy intensity because the substitution of capital for energy reduced energy intensity to a great extent.These findings were obtained at the national level and varied at die regional level.     

A strategic view of the world energy problem

This paper reviews the current energy supply and consumption. Worldwide, there was an increase in the annual energy consumption of 5% between 1955 and 1973 and of 2.7% between 1973 and 1979, but there was a decrease of 0.2% from 1979 to 1983. The role of oil grew from 31% to 47% of world energy consumption between 1955 and 1973 but dropped to 40.3% in 1983. Despite an overall decline in energy consumption in the last few years, the consumption of electricity continues to grow. Nuclear energy has not completely recovered from the crisis of the second half of the 1970's. This is in part because of social acceptance factors and hostility to large plants. World energy problems will continue over the next 20 years. A comprehensive approach is needed which stresses renewable energy and nuclear fission.     

The energy consumption of Paris and its supply areas from the eighteenth century to the present

Since the eighteenth century and the industrial revolution, cities have experienced great changes in their metabolism, and particularly in their energy consumption: transitions from one energy source to another, growing per capita consumption, and total consumption to cite but a few. These changes also impact urban energy supply areas and supply distance. This paper estimates Paris??s energy demand in both final and primary terms since the eighteenth century and gives an illustration of long-term socio-ecological interactions in an interdisciplinary perspective, connecting energy flow analysis, and historical research. It gives an overview of energy supply areas and assesses the distance between supply sites and the city. Paris??s annual total energy requirement (TER) was about 19?GJ per capita at the beginning of the eighteenth century and reached 30?GJ per capita in 1800; the supply area remained nearly the same with an average supply distance (D_avg) of 200?km. During the nineteenth century, Paris??s population increased fivefold, and energy transitioned from biomass to fossil fuel. Per capita TER remained stable, whereas Paris??s supply area moved progressively toward coal basins, in connection with the tremendous change in transport systems. As a consequence, the D_avg grew to 270?km around 1870. During the twentieth century, and especially since the Interwar period, per capita TER increased considerably (to 26?GJ/cap/year in 1910, 47?GJ/cap/year in 1946 and 126?GJ/cap/year in 2006). The internationalization of the energy supply and the shift to petroleum and natural gas also increased the remoteness of the supply sites: the D_avg equaled 3850?km in 2006.     

Threshold effects of renewable energy consumption on economic growth under energy transformation

China proposed that non-fossil energy consumption account for 20% in total energy consumption. EU increased the target of renewable energy consumption share from 27% to 35% in 2030.Energy transformation and increasing renewable energy consumption are important energy strategies for all countries at present. Then, is the impact of renewable energy consumption on economic growth positive or negative? Are there any differences in the direction or magnitude of the impact among countries or regions, and what are the determinants behind them? We apply panel threshold effect model to test threshold effects of renewable energy consumption on economic growth of EU. Empirical result shows: first, the impact of renewable energy consumption on economic growth is negative. Second, renewable energy consumption has significant threshold effects on economic growth. Third, now, energy consumption intensity and GDP per capita of most EU members are in the appropriate threshold regimes. In contrast, more and more EU members are in the high-subsidy group. Fourth, the average annual growth rates of renewable energy consumption showed no significant difference between high-subsidy and lowsubsidy countries from 1990 to 2014. Therefore, subsidy with high economic cost is not the onlyeffective means to increase renewable energy consumption.     

Limitations on the renewability of renewable energy resources

The primary supposition about renewable forms of energy is that use of such resources will not result in depletion or exhaustion. While it is true that natural energy flows such assun and wind are not directly subject to degradation by use, there may still be indirect limitations on renewability. The exploitation of natural energy flows may require that systems of nonrenewable “support” resources be used to capture, store, and convert natural energy into useful forms. Poor resource management practices that degrade the support resources may therefore, in effect, endanger renewability. Biomass is an illustrative case of a renewable energy resource with nonrenewable support components. The soil and water management practices of American agriculture, a large-scale biomass production system, are resulting in serious degradation and depletion of these vital system elements. This degradation represents a threat to the future of biomass food and energy supplies.     

The EU sustainable energy policy indicators framework

The article deals with indicators framework to monitor implementation of the main EU (European Union) directives and other policy documents targeting sustainable energy development. The main EU directives which have impact on sustainable energy development are directives promoting energy efficiency and use of renewable energy sources, directives implementing greenhouse gas mitigation and atmospheric pollution reduction policies and other policy documents and strategies targeting energy sector. Promotion of use of renewable energy sources and energy efficiency improvements are among priorities of EU energy policy because the use of renewable energy sources and energy efficiency improvements has positive impact on energy security and climate change mitigation. The framework of indicators can be developed to establish the main targets set by EU energy and environmental policies allowing to connect indicators via chain of mutual impacts and to define policies and measures necessary to achieve established targets based on assessment of their impact on the targeted indicators representing sustainable energy development aims. The article discusses the application of indicators framework for EU sustainable energy policy analysis and presents the case study of this policy tool application for Baltic States. The article also discusses the use of biomass in Baltic States and future considerations in this field.     

Practical consequences of the assessment of different energy health risks

Public authorities must make decisions about energy, and the risks of alternative strategies need to be calculated including health and environmental costs. Information from various sources must be organized into a logical framework for comparing impacts. This must include the widest practicable range of health and environmental damage — public-health impact of pollution, role of accidents, disease and hazardous materials in the workplace, and odds for catastrophes. It must put each part of the energy cycle into perspective-giving particular attention to uncertainties in knowledge - to convey what is known, what is uncertain, and the importance of each factor in the overall picture. This paper gives examples of the use of health-impact assessment by decisionmakers: (1) comparative risk assessment of the health effects of coal and nuclear fuel cycles used in nuclear power plant siting and licensing hearings, and (2) health risks of acid deposition and other air-transported pollutants, carried out as part of an assessment for the U.S. Congress Office of Technology Assessment.     

中国农村能源正义的法律实现

为了厘清中国能源正义的现况,为《能源法》的制定提供直接参考,本文选择中国农村能源正义作为具体的研究对象,主要采用规范分析的研究方法,从能源正义和农村能源正义的概念界定入手,描述了中国农村能源不正义的事实现况和法律现况,指出了中国农村环境正义法律实现的路径,并阐释了法律实现的关键。本文认为,农村能源正义是指,能源的所有方、供给服务方、消费方等主体不因其农民的身份性质、农村的地域分布和农业的禀赋强弱等因素,而应在能源的勘探开发、加工转换、仓储运输、供给服务等领域享有平等的对待和实质的参与;农村能源不正义的事实现况主要表现为农村能源并未全面体现能源的自然、经济、安全和生态等多维价值,而其法律现况则主要表现为现有的能源立法并未对农村能源在分配、程序、矫正和社会正义上做系统的表达。本文指出,中国农村能源正义法律实现的路径,其逻辑起点在于保障农民的能源权,应首先从法律上正面规定公民的能源权,进而采用《能源法》的集中表达与相关法律部门的分散表达相结合的具体方式和步骤。本文建议,中国农村能源正义法律实现的关键是科学制定《能源法》,首先要明确其核心地位,处理好与《农业法》等法律部门之间的关系;其次要在总则中,重述立法目的、规定公民能源权、完善能源普遍服务;最后在《能源法》的分则中专设"农村能源"的章节,整合现有的《能源法(征求意见稿)》的内容,并从原则、规划、保障、生态化、公众参与、授权、救济、法律责任等方面进行优化。     

Agroecosystem energy transitions in the old and new worlds: trajectories and determinants at the regional scale

Energy efficiency in biomass production is a major challenge for a future transition to sustainable food and energy provision. This study uses methodologically consistent data on agroecosystem energy flows and different metrics of energetic efficiency from seven regional case studies in North America (USA and Canada) and Europe (Spain and Austria) to investigate energy transitions in Western agroecosystems from the late nineteenth to the late twentieth centuries. We quantify indicators such as external final energy return on investment (EFEROI, i.e., final produce per unit of external energy input), internal final EROI (IFEROI, final produce per unit of biomass reused locally), and final EROI (FEROI, final produce per unit of total inputs consumed). The transition is characterized by increasing final produce accompanied by increasing external energy inputs and stable local biomass reused. External inputs did not replace internal biomass reinvestments, but added to them. The results were declining EFEROI, stable or increasing IFEROI, and diverging trends in FEROI. The factors shaping agroecosystem energy profiles changed in the course of the transition: Under advanced organic and frontier agriculture of the late nineteenth and early twentieth centuries, population density and biogeographic conditions explained both agroecosystem productivity and energy inputs. In industrialized agroecosystems, biogeographic conditions and specific socio-economic factors influenced trends towards increased agroecosystem specialization. The share of livestock products in a region’s final produce was the most important factor determining energy returns on investment.

     

Stakeholder requirements for building energy efficiency in mass housing delivery: the House of Quality approach

Threats of climate change and future energy price uncertainty have led to a global debate on energy efficiency, particularly the energy efficiency of housing projects. This serious global problem calls for improvement in energy efficiency from all sectors, especially the building sector which is considered a major energy consumer. Adoption of energy efficiency design practices in the housing sector has been perceived to have a significant potential to contribute greatly to the sustainable building process. Additionally, most studies indicate that the understanding and integration of stakeholder requirements has an enormous potential towards increasing the sustainability perspectives that relate to social, environmental, economic and technical issues of buildings. However, there is enough evidence from several studies suggesting a lack of common perspective on stakeholder requirements towards building energy efficiency (BEE) in housing development. Hence it is argued that stakeholders’ alignment for energy efficiency improvement is crucial and a fundamental challenge that needs to be addressed if the goal of energy use reduction in buildings is to be achieved. The aim of this paper is to identify the important building energy requirements among stakeholders of mass housing projects and their impact on technical characteristics of mass housing projects. Through a survey of building industry stakeholders and using the House of Quality model for analysis of the data obtained, the study identified five (5) most rated BEE stakeholders’ requirements in respect of housing development. The study gives a new insight into the considerations of building stakeholders regarding energy efficiency. This insight is useful towards achieving sustainable building solutions that meet the sustainability features of housing development in Ghana and other countries with similar energy and housing challenges.     

Geopolitics of global climate change and energy security

Currently,the problem of climate change is already far beyond the category of scientific research,and it affects the economic operation mode,interests pattern,and geographical relationships and becomes the focus of global governance.During the transition period of the international economic and social development and the critical transformation period of the world geopolitical pattern reorganization,China’s industrialization is still at the intermediate stage,and tackling with climate change is also China’s internal demand under this development stage.With more influence of climate change on national competitiveness,climate change and geopolitics present complex multiple relations,and climate change in the era of geopolitical landscape gradually affected the national strategy and diplomacy.This article offered some relevant suggestions based on evaluating the new geopolitical characteristics of climate change:(1)weighing of interests and properly handling the complex relations among major powers during international climate negotiations;(2)strengthening risk judgments and actively cooperating with the United States and the European Union on energy and climate change;(3)relying on the"One Belt(Silk Road Economic Belt)and One Road(twenty-first century Maritime Silk Road)"to ensure China’s energy security and actively participating in the global energy governance;(4)strengthening the"south-south cooperation"mechanism innovation and increasing the investment.     

Sustainable energy generation using hybrid energy system for remote hilly rural area in India

Hybrid energy systems are renewable energy system combined in a complementary fashion to ensure dependable power supply at competitive cost. Diesel generators (DGs) are also added here as a back-up source of supply. For remote areas far from a transmission grid, these systems can provide a reliable and cost-effective supply. Addition of DG could instigate environmental pollution in such remote unpolluted areas. In the present work, optimal sizing of hybrid energy system has been attempted for a remote village cluster of Uttarakhand (India) to make available desired power supply at minimum environmental effluence. Hybrid Optimization Model for Electrical Renewable (HOMER) software from National Renewable Energy Laboratory, USA has been employed to attain the objective. The software offered several feasible systems, ranked on the basis of net present cost (NPC). All such systems are further analysed for emissions they have made in the environment. Hence, the optimal system fulfilling the criteria of minimal environmental degradation with sufficiently minimum NPC has been searched for. In the present work, the most appropriate system offered on the basis of NPC is the one which has five wind turbines (10 kW each), one DG (65 kW) and 25 batteries (6 V, 6.94 kW h each). The NPC of the system is $1,252,018, whereas its initial capital cost and levelised cost of energy (COE) are $94,233 and $0.292/kW h, respectively. After further analysis of all the feasible systems on the basis of environmental effluence, the most feasible system explored is the one which has minimal emissions of various pollutants such as carbon dioxide, carbon monoxide, hydrocarbon, particulate matter, sulphur dioxide and nitrous oxide. The system has been obtained on a compromised NPC of $1,270,921 with a capital cost of $148,133 and COE of $0.296/kW h. Components of the system include five wind turbines (10 kW), a 9 kW PV panel and a 65 kW DG along with 30 batteries (6 V, 6.94 kW h each). The system so obtained would prove to be a feasible, optimally sized and sustainable power supply alternative for remote unelectrified hilly rural area.     

可持续能源转型:模型构建与分析

为研究可持续能源系统转型路径,以转型理论为概念框架,从宏观、中观和微观多层次对能源系统进行分析,建立了基于代理的系统动力学转型模型。模型选取当前能源消费结构中占较大比重的煤炭、石油、天然气、风能、水电、光伏和核能作为复杂代理,选取消费者作为简单代理,根据中国能源数据对其进行参数化,并模拟运行了能源系统从2016—2050年间各种类型能源消费比重变动的情形。研究结果显示:①外部景观信号的输入对于能源系统的可持续转型有着至关重要的作用。随着景观信号的输入,各类能源的相对比重发生复杂的相互作用,景观信号持续时间越长、强度越大,向可持续能源系统转型的速度越快、规模越大。②到2050年,可持续能源将占一次能源消费比重的60%左右,实现能源系统的可持续转型,其中,水电将在能源系统的可持续化转型中发挥重要的作用。③2030年以前,石油和天然气将是能源系统中煤炭消费比重下降的主要替代品,因为它们的应用技术已经发展成熟,而且它们更适应当前的基础设施,从短期来看相比可持续能源石油和天然气更有优势,在这种情形下,仍然需要继续支持可持续能源的发展,否则能源系统的可持续转型将不会发生。该研究主要探索通过当前能源系统的景观压力强度以及转型的进度,来量化未来需要输入的景观压力强度;通过模拟转型发生的具体情景,对转型的进展进行更清楚的界定,借此来评估二氧化碳的排放路径;模拟模型也可以评估各类能源在不同时间点上的各种可能性,以及探索各类可持续能源的发展潜力。